The broad scope of this P01 is to test the hypothesis that human genotype influences energy metabolism, and as a consequence contributes to healthy aging. The objective of this project is to test the hypothesis that indicators of vascular status (e.g., brachial artery vasoreactivity and carotid intimal thickness) are associated with measures of physical function. This project of the P01 contributes to the overall scope of the program by exploring the biological plausibility that metabolism and oxidative stress exert an influence on function and consequently healthy aging via cardiovascular impairment. Therefore, this project specifically seeks funding for the inclusion of ultrasonographic imaging of carotid and brachial arteries. The investigators presently have funding for the assessment of physical function using the Continuous Scale-Physical Function Performance Task (CS-PFP), as well as handgrip strength, tapping speed, and ADL inventories. However, the investigators seek funding to enhance the information acquired during the functional assessment by collecting breath gas measures during the CS-PFP. This will allow the investigators to derive the oxygen uptake efficiency slope (DUES), which will serve as an index of cardiorespiratory capacity. Finally, the investigators propose to include a pilot exercise-training study to test the hypothesis that changes in vascular status will result in changes in physical function. While this project has important project specific hypotheses, the inclusion of measures of vascular and physical function will also provide numerous opportunities for synergy with the other projects, as described herein.